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Re: Replication delay

El 21/3/19 a las 22:51, Quanah Gibson-Mount escribió:
--On Thursday, March 21, 2019 9:22 AM +0100 "Ángel L. Mateo" <amateo@um.es> wrote: 


    I've been running MMR (not delta) for years too without problems too.
    Now the server with problems works without problems for days, but then 
it start delaying syncs.

    The problem I have is that I don't know how to debug it.

    Is there any documentation about how to debug it? about the sync logs
messages?
I think one of the key differences to understand between syncrepl and delta-syncrepl is that syncrepl will simply overwrite entries that have discrepencies while delta-syncrepl will go into REFRESH mode.  Since you started out with an OpenLDAP version that has numerous replication bugs, it may be your masters are not in accordance with one another, and the "delays" you are seeing are actually systems going into refresh. 


	replication is using syncrepl, not delta-syncrepl.
The first thing you should look at is if there are any instances of REFRESH in your logs, something along the lines of: 

do_syncrep2: rid=001 delta-sync lost sync, switching to REFRESH
If you see that, the issue isn't delayed replication, the issue is that your databases are out of sync. 


	I can't find that exact message, but I have these in the consumer:
Mar 21 10:00:26 canis41 slapd[68402]: do_syncrep2: rid=039 LDAP_RES_INTERMEDIATE - REFRESH_PRESENT Mar 21 10:40:56 canis41 slapd[68402]: do_syncrep2: rid=039 LDAP_RES_INTERMEDIATE - REFRESH_PRESENT Mar 21 15:45:52 canis41 slapd[68402]: do_syncrep2: rid=039 LDAP_RES_INTERMEDIATE - REFRESH_PRESENT
If you don't see instances of REFRESH mode being triggered in your log, we can discuss further what the logs indicate and other things that may need looking at. 



--
Angel L. Mateo Martínez
Sección de Telemática
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